Microcystin production during algal bloom occurrence in Laguna de Bay, the Philippines   总被引：1，自引：0，他引：1  

SUSANA F  BALDIA    MA CECILIA  G CONACO  TOSHITAKA  NISHIJIMA  SUSUMU  IMANISHI  KEN-ICHI  HARADA 《Fisheries Science》2003,69(1):110-116

ABSTRACT:   The amount of microcystin in Microcystis aeruginosa bloom was investigated during the rainy season of 1999 in Laguna de Bay, the Philippines. Bloom samples taken from the West Bay and East Cove stations of the lake were studied in relation to the characteristics of environmental conditions. Four types of microcystins, microcystin-LR (MC-LR), microcystin-RR (MC-RR), 6(Z)-Adda-microcystin-RR, and 3-desmethylmicrocystin-LR were identified from the natural bloom samples among which MC-LR was the most dominant type of microcystin. Production of microcystin (88.6 µg/100 mg dried cells) was highest during the first sampling week that coincided with high water transparency and high conductivity. The occurrence of a strong typhoon during the second sampling week had changed the environment drastically, which was characterized by low water transparency, high turbidity, low water temperature, and with trace amounts of MC-LR detected at the East Cove station. Thus, toxin production over time as well as the relationship between Microcystis production and toxin concentration could not be fully evaluated.  相似文献   

Enhancement of resistance to vibriosis in rainbow trout, Oncorhynchus mykiss (Walbaum), by oral administration of Clostridium butyricum bacterin   总被引：1，自引：0，他引：1  

M. SAKAI  T. YOSHIDA  S. ATSUTA  M. KOBAYASHI 《Journal of fish diseases》1995,18(2):187-190

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Refined calculation model for NaLA, a fishing net shape simulator, applicable to gill nets   总被引：1，自引：0，他引：1  

Takashi  SHIMIZU  Tsutomu  TAKAGI  Katsuya  SUZUKI  Tomonori  HIRAISHI  Katsutaro  YAMAMOTO 《Fisheries Science》2004,70(3):401-411

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Preparation of algal-oligosaccharide mixtures by bacterial agarases and their antioxidative properties   总被引：1，自引：0，他引：1  

Shao-Chi  WU  Chorng-Liang  PAN 《Fisheries Science》2004,70(6):1164-1173

ABSTRACT:   Algal-oligosaccharide-lysates (AOL), derived from six agars and four algal polysaccharide extracts (APE), were treated with 100–500 activity units (AU) of MA103-agarases or MAEF108-agarases, and their antioxidative properties evaluated. Soluble total polyphenols (TP) were between 462.2 ± 1.6 gallic acid equivalents (GAE, µg/mL) and 70.6 ± 17.4 GAE. The DPPH radical scavenging capacity of all AOL went from 68.3 ± 0.7% to 0.5 ± 0.1%. The ferrous ion chelating capacity of all AOL went from 93.1 ± 0.2% to 21.7 ± 0.9%. Evaluation of the H₂O₂ scavenging capacity of all AOL was between 35.9 ± 5.4% and 0.1 ± 0.2%. The reducing power of all AOL went from 51.3 ± 2.6 to 3.2 ± 6.8 expressed as µg/mL ascorbic acid. In DPPH radical scavenging capacity, ferrous ion chelating capacity and reducing power etc., the AOL derived from the APE of Porphyra dentate (digested by 500 AU of MAEF108-agarases) were highest, in all test sets. However, the AOL derived from the APE of Monostroma nitidum (digested by 500 AU of MAEF108-agarases) had the highest H₂O₂ scavenging capacity in all test sets. The order of antioxidative activity performance of all AOL treated in this experiment, by these four antioxidative methods, is as follows: ferrous ion chelating capacity > DPPH radical scavenging capacity > H₂O₂ scavenging capacity > reducing power; this may be related to their polyphenols, small molecular weight polysaccharides or simple sugar constituents. In this study, it is demonstrated that various agarases derived from algal oligosaccharide mixtures possess good potential for use as a health food, due to their antioxidative capacity.  相似文献   

Comparison of oxygen consumption patterns between wild and cultured black rockfish Sebastes schlegeli   总被引：1，自引：0，他引：1  

SEONG-JIN  YOON  CHONG-KWAN  KIM  JUNG-GOO  MYOUNG  WAN-SOO  KIM 《Fisheries Science》2003,69(1):43-49

ABSTRACT:   To compare metabolic activity rhythms between wild and cultured black rockfish Sebastes schlegeli , we measured long-term oxygen consumption rates (OCR) using an automatic intermittent-flow respirometer under constant temperature and darkness. Oxygen consumption rates peaked among wild black rockfish at 12.4 h intervals, which corresponded to a circatidal rhythm. The wild fish were probably exhibiting responses that corresponded to tidal events in their natural environment. However, when captured wild black rockfish were kept under laboratory conditions (12 h light [L] : 12 h dark [D]) for 30 days, the OCR shifted to a circadian rhythm (24.1–24.9 h). The OCR of cultured black rockfish that had been reared in a tank for 9 months peaked at approximately 24 h intervals, corresponding to a circadian rhythm. The results of this study suggest that the differences in OCR patterns between wild and cultured fish were mainly due to differences in the environmental conditions between tidal and non-tidal habitats.  相似文献   

Estimating codend selectivity and fish escapement from a covernet of an insufficiently small mesh size     

T AKAHISA  MITUHASI  T ADASHI  TOKAI  R UBÉN  ERCOLI  J ULIO C.  GARCÍA  L UIS  SALVINI  J UAN  BARTOZZETTI  R ICARDO  ROTH 《Fisheries Science》2000,66(2):327-333

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Allo-eudiploidy of the diploid cells in diploid-tetraploid mosaic hybrids between female rainbow trout Oncorhynchus mykiss and male amago salmon O. rhodurus     

Xuelian  ZHANG  Hiroshi  ONOZATO 《Fisheries Science》2004,70(5):924-926

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Gastric evacuation in koayu Plecoglossus altivelis altivelis examined in aquaria     

Machiko  NISHINO  Keiichi  KAWABATA 《Fisheries Science》2003,69(4):819-822

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Lipid biosynthesis from [¹⁴C]-glucose in the coral Montipora digitata     

Hirosuke  OKU  Hideyuki  YAMASHIRO  Kyoko  ONAGA 《Fisheries Science》2003,69(3):625-631

ABSTRACT:     Glucose has been implicated in functioning as a form of carbon translocated from symbiont zooxanthellae to the host coral cell. The present paper describes the lipid biosynthesis from [¹⁴C]-glucose in the coral tissue. To study the incorporation of [¹⁴C]-glucose into lipids, the branch tips of the coral Montipora digitata were incubated with [¹⁴C]-glucose or another radiolabeled substrates. The lipid biosynthesis from [¹⁴C]-glucose was dependent on light, and was decreased by dark conditions or by photosystem II inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Of the lipid classes, the light dependency was more pronounced with the biosynthesis of triacylglycerols (TG) and wax compared with phospholipids. Examination of [¹⁴C]-label distribution in the glycerolipids suggested that [¹⁴C]-glucose supplied mainly the fatty acid moiety of newly synthesized TG, while [¹⁴C]-glucose provided evenly the fatty acid moiety and the glycerol skeleton of phospholipids. The comparison of [¹⁴C]-labeling of lipid from host coral tissue and symbiont zooxanthellae suggested that [¹⁴C]-glucose entered the coral cell and was processed in parallel in the zooxanthellae and host cells. Furthermore, the coral cells used various [¹⁴C]-labeled sugars for lipid synthesis with similar lipid labeling profile as was the case for glucose. The current study thus supports the view that the low-molecular-weight compound, sugars and amino acids, once translocated from zooxanthellae to host cell were metabolized toward lipogenesis as well as glycerol.  相似文献   

Characterization of the goldfish fecal microflora by the fluorescent in situ hybridization method     

MAIDIE  ASFIE  TORU  YOSHIJIMA  HARUO  SUGITA 《Fisheries Science》2003,69(1):21-26

ABSTRACT:   Bacterial populations in goldfish feces were characterized by the fluorescent in situ hybridization (FISH) method. A total of nine different group-specific rRNA-targeted oligonucleotide probes were used. Approximately half of the microbial cells (57.8 ± 16.7%) were detected with a probe EUB338 and found to be bacteria. The microbial cells in 33–35 of the 35 samples from five specimens strongly hybridized with probes ALF1b, BET42a and GAM42a, suggesting that goldfish intestinal bacteria are mainly composed of α, β and γ-subclasses of Proteobacteria. The fact that a probe AER66 reacted with 25.6 ± 14.2% of the total microbial cells in all 35 samples, demonstrated that genus Aeromonas was the dominant species in the goldfish intestines. Genus Bacteroides including Bacteroides type A detected with a probe BAC303 was observed in 15 of 35 samples while other taxonomic groups determined with HGC69a, CF39a and P72 were detected in 6–11 of 35 samples. These results strongly suggest that Bacteroides shows the greatest daily fluctuation and interindividual variation in the intestines of goldfish. Moreover, the FISH method was proven to be useful for rapid enumeration of taxonomic groups of fish intestinal bacteria.  相似文献